Traditional aircraft structural materials are predominantly metallic and so the dissipation of lightning strikes and static discharge induced by, for example, electrical cables is relatively straight-forward, as currents are able to freely flow through the metallic structure.
The hybrid of metallic and composite materials in aircraft currently under development brings about particular challenges, as the polymers used in high performance composites generally have low electrical conductivity. Electrical current flows within these hybrid structures therefore need to be managed and controlled so as to avoid the creation of “hot spots” and localised impact damage.